Fingerprint capture system, fingerprint capture device, image processing apparatus, fingerprint capture method, and storage medium

ABSTRACT

A fingerprint capture system, a fingerprint capture device, an image processing apparatus, a fingerprint capture method, and a storage medium that can acquire a high quality fingerprint image are provided. A disclosed example includes: a capture unit that captures a fingerprint; an image processing unit that processes a transferred fingerprint image captured by the capture unit; a display unit on which the fingerprint image transferred to the image processing unit is displayed; a recording unit where the fingerprint image transferred to the image processing unit is recorded by the image processing unit; and an instruction unit that inputs, in the image processing unit, a record instruction that instructs the image processing unit to record the fingerprint image in the recording unit. The image processing unit records, in the recording unit, the fingerprint image displayed on the display unit at the time the record instruction is input by the instruction unit.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No.15/760,862 filed Mar. 16, 2018, which is a National Stage ofInternational Application no. PCT/JP2016/004226 filed Sep. 16, 2016,claiming priority based on Japanese Patent Application no. 2015-186010,filed Sep. 18, 2015. The contents of all of which are incorporated byreference herein.

TECHNICAL FIELD

The present invention relates to a fingerprint capture system, afingerprint capture device, an image processing apparatus, a fingerprintcapture method, and a storage medium.

BACKGROUND ART

Fingerprints have uniqueness and permanence because fingerprints aredifferent among individuals and do not change in their lifetime. Thus,fingerprints have been widely used in the situations whereidentification of an individual is required. An optical device thatcaptures a fingerprint by using a two-dimensional image sensor such as aComplementary Metal Oxide Semiconductor (CMOS) image sensor or the likeis known as one of the devices for acquiring such a fingerprint.

Among the optical devices that capture a fingerprint by using an imagesensor, a transmission type fingerprint input device has been focused on(see Patent Literature 1). In a transmission type fingerprint inputdevice, a light from a light source is caused to enter a finger and isscattered therein, and a light exiting from the surface of the finger isutilized to capture an image of a fingerprint.

CITATION LIST Patent Literature

PTL 1: Japanese Patent No. 3751872

SUMMARY OF INVENTION Technical Problem

When a fingerprint is captured, however, the quality of a capturedfingerprint image may vary due to a condition or the like at thecapturing, and thus a low quality fingerprint image may be obtained.Since a low quality fingerprint image makes identification of anindividual difficult, it is desirable for a fingerprint image to be of ahigher quality as much as possible. An example of a low qualityfingerprint image may be an image with an insufficient contrast betweena ridge line part and a valley line part of a fingerprint or an imagewith uneven brightness. Further, an example of a low quality fingerprintimage may be an image in which a part of a fingerprint may be deleted asa result of misalignment of a finger with respect to a region that canbe captured by an image sensor at the capturing.

The present invention has been made in view of the above problem andintends to provide a fingerprint capture system, a fingerprint capturedevice, an image processing apparatus, a fingerprint capture method, anda storage medium that can acquire a high quality fingerprint image.

Solution to Problem

According to an example aspect of the present invention, provided is afingerprint capture system including: a capture unit that captures afingerprint; an image processing unit to which a fingerprint image ofthe fingerprint captured by the capture unit is transferred and thatprocesses the fingerprint image; a display unit on which the fingerprintimage transferred to the image processing unit is displayed; a recordingunit in which the fingerprint image transferred to the image processingunit is recorded by the image processing unit; and an instruction unitthat inputs, in the image processing unit, a record instruction thatinstructs the image processing unit to record the fingerprint image inthe recording unit, and the image processing unit records, in therecording unit, the fingerprint image displayed on the display unit atthe time when the record instruction is input by the instruction unit.

According to another example aspect of the present invention, providedis a fingerprint capture device including: a sensor unit that captures afingerprint; a transfer unit that, in order to display a fingerprintimage of the fingerprint captured by the sensor unit on a display unit,transfers the fingerprint image to an image processing unit; and aninstruction unit that inputs, into the image processing unit, a recordinstruction that instructs recording of the fingerprint imagetransferred to the image processing unit and displayed on the displayunit into a recording unit.

According to yet another example aspect of the present invention,provided is an image processing apparatus including: a receiving unitthat receives a fingerprint image of a fingerprint captured by a captureunit that captures the fingerprint; a display control unit that displaysthe fingerprint image received by the receiving unit on a display unit;and a recording control unit that, based on a record instruction thatinstructs recording of the fingerprint image displayed on the displayunit in a recording unit, records the fingerprint image in the recordingunit.

According to yet another example aspect of the present invention,provided is a fingerprint capture method including: capturing afingerprint; transferring a fingerprint image of the capturedfingerprint; displaying the transferred fingerprint image; recording thetransferred fingerprint image; and inputting a record instruction thatinstructs recording of the fingerprint image, and the recording of thefingerprint image records the fingerprint image displayed at the timewhen the record instruction is input.

According to yet another example aspect of the present invention,provided is a storage medium in which a program is stored, the programcausing a computer that processes a fingerprint image transferred from afingerprint capture device that captures a fingerprint to execute:displaying a fingerprint image transferred from the fingerprint capturedevice; and recording the fingerprint image transferred from thefingerprint capture device, and the recording records the fingerprintimage displayed at the time when a record instruction that instructsrecording of the fingerprint image is input.

Advantageous Effects of Invention

According to the present invention, a high quality fingerprint image canbe acquired.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram illustrating a fingerprint capture systemaccording to a first example embodiment of the present invention.

FIG. 2 is a sectional view illustrating a fingerprint capture device inthe fingerprint capture system according to the first example embodimentof the present invention.

FIG. 3 is a schematic diagram illustrating a view in which an assistingperson holds the fingerprint capture device in the fingerprint capturesystem according to the first example embodiment of the presentinvention to capture a fingerprint of a finger of a subject.

FIG. 4 is a block diagram illustrating the fingerprint capture device inthe fingerprint capture system according to the first example embodimentof the present invention.

FIG. 5 is a block diagram illustrating an image processing apparatus inthe fingerprint capture system according to the first example embodimentof the present invention.

FIG. 6 is a schematic diagram illustrating a display window displayed onthe image processing apparatus in the fingerprint capture systemaccording to the first example embodiment of the present invention.

FIG. 7 is a flowchart illustrating a basic operation of the fingerprintcapture system according to the first example embodiment of the presentinvention.

FIG. 8 is a timing chart illustrating the operation of the fingerprintcapture device and the image processing apparatus of the fingerprintcapture system according to the first example embodiment of the presentinvention.

FIG. 9 is a timing chart illustrating the operation of a fingerprintcapture device and an image processing apparatus of a fingerprintcapture system according to a second example embodiment of the presentinvention.

FIG. 10 is a timing chart illustrating the operation of a fingerprintcapture device and an image processing apparatus of a fingerprintcapture system according to a third example embodiment of the presentinvention.

FIG. 11 is a timing chart illustrating the operation of a fingerprintcapture device and an image processing apparatus of a fingerprintcapture system according to a fourth example embodiment of the presentinvention.

FIG. 12 is a block diagram illustrating a functional configuration of afingerprint capture system according to another example embodiment ofthe present invention.

FIG. 13 is a block diagram illustrating a functional configuration of afingerprint capture device according to another example embodiment ofthe present invention.

FIG. 14 is a block diagram illustrating a functional configuration of animage processing apparatus according to another example embodiment ofthe present invention.

DESCRIPTION OF EMBODIMENTS First Example Embodiment

A fingerprint capture system and a fingerprint capture method accordingto a first example embodiment of the present invention will be describedby using FIG. 1 to FIG. 8.

First, the general configuration of the fingerprint capture systemaccording to the present example embodiment will be described by usingFIG. 1. FIG. 1 is a schematic diagram illustrating the generalconfiguration of the fingerprint capture system according to the presentexample embodiment.

As illustrated in FIG. 1, a fingerprint capture system 1 according tothe present example embodiment has a fingerprint capture device 10 thatcaptures a fingerprint of a subject and an image processing apparatus 20that performs processes such as display, recording, or the like on afingerprint image that is an image of a fingerprint captured by thefingerprint capture device 10. The image processing apparatus 20 has adisplay 214 that displays a fingerprint image. The fingerprint capturedevice 10 is communicably connected to the image processing apparatus 20via the communication cable 30. Note that the fingerprint capture device10 may be communicably connected to the image processing apparatus 20 byusing a wireless scheme instead of a wired scheme through thecommunication cable 30.

A subject whose fingerprint is captured by the fingerprint capturesystem 1 according to the present example embodiment is not limited inparticular, and any age of persons including a newborn, an infant, ayoung child, or the like whose finger is too thin, too small, too soft,or the like, which makes it difficult to capture their fingerprints, canbe a subject. Note that it is impossible or difficult for a newborn, aninfant, a young child, or the like to capture the fingerprint byhimself/herself alone. When it is necessary to capture a fingerprint ofsuch a subject who is incapable of or has difficulty in capturing thefingerprint by himself/herself alone, an adult or the like who iscapable of operating the device would be an assisting person to assistthe subject in capturing the fingerprint of the subject, as describedlater.

The fingerprint capture device 10 is an optical fingerprint scanner thatfunctions as a capture unit that captures a fingerprint image by using atwo-dimensional image sensor. The fingerprint capture device 10 cancapture a fingerprint image of any one of respective thumbs, indexfingers, middle fingers, ring fingers, and little fingers of the lefthand and the right hand of a subject, namely, the ten fingers in total,for example. Further, the fingerprint capture device 10 can capture afingerprint image of not only a finger of the hands but also any one ofrespective first toes, second toes, third toes, fourth toes, and fifthtoes of the left foot and the right foot, namely, the ten fingers offeet (toes) in total.

When a newborn, an infant, or a young child is a subject, for example,the fingerprint capture device 10 can be used to capture fingerprints ofa plurality of fingers or toes of a single subject and provide thesefingerprint images of the plurality of fingers or toes foridentification of an individual. In this case, for example, for a singlesubject, fingerprints of the thumb of the left hand, the thumb of theright hand, the first toe of the left foot, and the first toe of theright foot can be sequentially captured.

The specific configuration of the fingerprint capture device 10 will bedescribed below by using FIG. 2 to FIG. 4. FIG. 2 is a sectional viewillustrating the fingerprint capture device 10 and illustrates a crosssection in a plane along the longitudinal direction and the verticaldirection of the fingerprint capture device 10. FIG. 3 is a schematicdiagram illustrating a view in which an assisting person holds thefingerprint capture device 10 to capture a fingerprint of a finger of asubject. FIG. 4 is a block diagram illustrating the fingerprint capturedevice 10.

As illustrated in FIG. 2, the fingerprint capture device 10 has a thincasing 110 shaped in a flat, approximate rectangular parallelepiped. Asensor cover 120 having an outer surface serving as a sensor face 1202is provided on a top plate of the casing 110. The fingerprint capturedevice 10 has an imaging sensor 130 provided inside the casing 110 viathe sensor cover 120, a pair of near-infrared light sources 140 providedon the top plate of the casing 110, and a control circuit 150 providedinside the casing 110.

A casing 110 is a hollow member having an external shape of a verticallyflat, approximate rectangular parallelepiped, and the longitudinaldirection is a front-back direction. Note that the front part of thecasing 110 is tapered. The casing 110 is a resin member, for example.The external shape of the casing 110 is thin and narrow so that a personcapable of operating the device can hold it by one hand. Note that theexternal shape of the casing 110 is not limited to the external shape ofa flat, approximate rectangular parallelepiped, but any shape may beemployed.

A rectangular sensor cover 120 is provided to the front part of the topplate of the casing 110. In the sensor cover 120, the outer surfaceserves as the sensor face 1202 with which the ball of the finger whosefingerprint is to be captured comes into contact. The rectangular sensorcover 120 is provided to the front part of the top plate of the casing110 such that a pair of sides of the sensor cover 120 extend in thelongitudinal direction. The sensor cover 120 is formed of a plate-likemember whose material transmits a near-infrared light, for example,formed of a protection glass. Thereby, as described later, anear-infrared light is emitted from the near-infrared light source 140,enters a finger on the sensor cover 120, and is emitted from the ball ofthe finger after scattered inside the finger, and the scattered lightsthen enter the image sensor 130. The sensor cover 120 is contacted withthe ball of a finger of a subject who directs his/her fingertip to thesensor cover 120 from the front side of the casing 110 when capturing afingerprint.

The near-infrared light sources 140 are provided on the top plate of thecasing 110 on both sides of the sensor cover 120, respectively. Each ofthe near-infrared light sources 140 has a plurality of light emittingdiodes (LEDs) 1402.

The plurality of LEDs 1402 each emit a near-infrared light. Thewavelength of the near-infrared light emitted by the LED 1402 is 820 to980 nm, for example. The plurality of LEDs 1402 are provided so as to bealigned in lines in a longitudinal direction of the casing 110 with apredetermined spacing. Further, the plurality of LEDs 1402 are coveredwith a protective member having transparency to a near-infrared light.When capturing a fingerprint, each LED 1402 is turned on, near-infraredlights are emitted so as to expand upward from each LED 1402, and thefinger whose ball is in contact with the sensor cover 120 is irradiatedwith the near-infrared lights.

Note that each LED 1402 may be provided inclined so as to emit anear-infrared light in an obliquely upward direction of the sensor cover120 side. Further, the near-infrared light source 140 is not limited tothe light source having a plurality of LEDs 1402, and a linear lightsource extending in the longitudinal direction of the casing 110 may beused as the near-infrared light source 140.

The image sensor 130 as a sensor unit that captures a fingerprint isprovided inside the casing 110. The image sensor 130 is provided insidethe casing 110 so as to direct the capturing surface to the sensor cover120 provided on the top plate of the casing 110. The capturing surfaceof the image sensor 130 has a rectangular shape having a wider area thanthe ball of the finger (toe) whose fingerprint is to be captured. Theimage sensor 130 is configured to capture a fingerprint of a finger bylight-receiving, at a capturing surface, near-infrared lights that havebeen irradiated from the ball of a finger contacting with the sensorcover 120 and have passed through the sensor cover 120. The image sensor130 is a two-dimensional image sensor, for example, a CMOS image sensor.Further, other than the CMOS image sensor, a Charge Coupled Device (CCD)image sensor may be used as the image sensor. While the pixel densityand the number of pixels of the image sensor 130 are not limited inparticular, it is preferable that the density be high such as 1000 ppior higher, for example, and that the number of pixels be large whenconsidering a case of capturing a fingerprint of a newborn, an infant, ayoung child, and the like. Specifically, a large CMOS image sensor witha high pixel density and a large number of pixels that has a size of 2cm in width, 3 cm in length and a pixel density of 1270 ppi, forexample, can be used as the image sensor 130.

In the fingerprint capture device 10, the principle of a fingerprintbeing captured by the image sensor 130 is as follows. In capturing afingerprint, near-infrared lights are emitted from the near-infraredlight sources 140 with the ball of a finger being in contact with thesensor face 1202 of the sensor cover 120. The near-infrared lightsemitted from the near-infrared light sources 140 enter the finger on thesensor cover 120. The near-infrared lights entering the finger arescattered inside the finger and then emitted out of the finger from thesurface of the finger. The near-infrared lights emitted out of thefinger have different intensities in accordance with whether emittedfrom the ridge line part or emitted from the valley line part of thefingerprint.

Since the ridge line part of a fingerprint is in contact with the sensorface 1202 of the sensor cover 120, the near-infrared light emitted outof the finger from the ridge line part reaches and enters the imagesensor 130 at a relatively high intensity without significantattenuation. In contrast, since the valley line part of a fingerprint isnot in contact with the sensor face 1202, the near-infrared lightemitted out of the finger from the valley line part is scattered by anair layer present between the valley line part and the sensor face 1202.In addition, reflection and refraction occur due to the difference inthe refractive index at the interfaces between the skin and the air andbetween the air and the sensor cover. Thus, the near infrared lightemitted out of the valley line part is significantly attenuated comparedto the near infrared light emitted out of the ridge line part andreaches and enters the image sensor 130 at a relatively low intensity ordoes not even reach the image sensor 130.

As a result, a fingerprint image in which there is a difference inbrightness/darkness between the ridge line part and the valley line partof the fingerprint is captured on the image sensor 130. That is, in acaptured fingerprint image, the ridge line parts of the fingerprintappear as bright parts, and the valley line parts appear as dark parts.Accordingly, a fingerprint is captured by receiving near-infrared lightsscattered inside a finger emitted out of the finger by using the imagesensor 130.

The image sensor 130 that has captured a fingerprint of a finger outputsimage data forming a fingerprint image thereof. As described later,image data output from the image sensor 130 is transferred to the imageprocessing apparatus 20 via the control circuit 150 and then via thecommunication cable 30. The image processing apparatus 20 to which imagedata is transferred performs display, recording, or the like of thefingerprint image based on the transferred image data.

The rear portion of the casing 110 serves as a holding portion 1102 heldby a subject whose fingerprint is to be captured or an assisting personwho assists capturing of the finger of the subject in capturing afingerprint. In accordance with whether or not the subject whosefingerprint is to be captured is able to capture the fingerprint byhimself/herself alone, the attitude of the subject in capturing thefingerprint will be different as described below.

First, when a subject is a person who is able to capture the fingerprintby himself/herself alone such as an adult, for example, the subject cancause the ball of the finger whose fingerprint is to be captured to comeinto contact with the sensor face of the sensor cover 120 while holdingthe holding portion 1102 by a hand opposite to the finger whosefingerprint is to be captured. The subject can hold the holding portion1102 from the side such that, among the fingers of the hand holding theholding portion 1102, the thumb is positioned on the top plate side ofthe casing 110 and the four fingers other than the thumb are positionedon the bottom plate side of the casing 110, for example.

In contrast, for example, when a subject is a person who is unable tocapture or has difficulty in capturing the fingerprint byhimself/herself alone such as a newborn, an infant, a young child, orthe like, an assisting person can assist capturing of a fingerprint ofthe finger of the subject. The assisting person is an adult or a minorwho is able to operate the device by himself/herself alone. In thiscase, the assisting person holds the holding portion 1102 by one handand moves the fingerprint capture device 10 toward the thumb of thesubject whose fingerprint is to be captured. The assisting person canhold the holding portion 1102 from the side such that, among the fingersof the hand holding the holding portion 1102, the thumb is positioned onthe top plate side and the four fingers other than the thumb arepositioned on the bottom plate side of the casing 110, for example.Furthermore, as illustrated in FIG. 3, the assisting person can causethe ball of the finger of the subject to come into contact with thesensor face 1202 while using the other hand if necessary. Note that,although not illustrated in FIG. 3, the assisting person can use thefingertip or the like of his/her hand which holds the holding portion1102 to press the finger of the subject that is in contact with thesensor face 1202 and fix the position thereof.

A press button type capture switch 160 that functions as an instructionunit is provided in the middle of the bottom face of the holding portion1102 held by the subject or the assisting person. The capture switch 160is configured so that, when pressed down, it can instruct thenear-infrared light source 140 to be turned on or off, instruct theimage sensor 130 to capture a fingerprint, or instruct the imageprocessing apparatus 20 to record a fingerprint image. Signals input tothe fingerprint capture device 10 and image processing apparatus 20 inresponse to pressing down of the capture switch 160 will be describedlater. The subject or the assisting person holding the holding portion1102 can press down the capture switch 160 by any of the four fingerspositioned on the bottom face side of the casing 110 of the fingers ofthe hand holding the holding portion 1102 while still holding theholding portion 1102.

Further, the capture switch 160 is formed so as to be embedded in theholding portion 1102 such that the pressed down face of the captureswitch 160 and the bottom face of the holding portion 1102 aresubstantially flat. The capture switch 160 is provided so as not toproject with respect to the bottom face of the holding portion 1102 asillustrated, which can suppress erroneous pressing down of the captureswitch 160.

The control circuit 150 is accommodated inside the holding portion 1102of the casing 110. Further, a connector portion 170 to which thecommunication cable 30 is connected is provided in the side end portionon the rear side of the holding portion 1102.

FIG. 4 is a block diagram illustrating each unit of the fingerprintcapture device 10 described above and illustrates the details of theimage sensor 130, the near-infrared light source 140, and the controlcircuit 150.

As illustrated in FIG. 4, the image sensor 130 has a pixel array 1302and a timing generator 1304. Further, the image sensor 130 has avertical scanning circuit 1306, a column amplifier circuit 1308, ananalog-to-digital (A/D) converter circuit 1310, a horizontal scanningcircuit 1312, and a signal processing circuit 1314.

A plurality of pixels are provided in a matrix in the pixel array 1302.Each pixel has a photoelectric conversion element that generates a pixelsignal by photoelectrically converting an incident near-infrared light.The timing generator 1304 generates and outputs a timing signal used forcontrolling the vertical scanning circuit 1306 and the horizontalscanning circuit 1312. The vertical scanning circuit 1306 scans thepixels of the pixel array 1302 on a pixel row basis. The columnamplifier circuit 1308 amplifies pixel signals read out by scansperformed by the vertical scanning circuit 1306. The A/D convertercircuit 1310 converts pixel signals amplified by the column amplifiercircuit 1308 from analog signals to digital signals. The horizontalscanning circuit 1312 performs scans on a pixel column basis to read outpixel signals converted by the A/D converter circuit 1310 to theoutside. The signal processing circuit 1314 performs predeterminedsignal processing on the pixel signal read out by the horizontalscanning circuit 1312 and output from the A/D converter circuit 1310 tooutput image data forming a fingerprint image. The image data outputfrom the signal processing circuit 1314 is input to the control circuit150.

In the near-infrared light source 140, a current limiting resistor 1406that restricts a current flowing in the LED 1402 and a transistor 1408that serves as a switch are connected to each of the plurality of LEDs1402.

One of the terminals of the current limiting resistor 1406 is connectedto the anode side terminal of each LED 1402. The collector of eachtransistor 1408 is connected to the cathode side terminal of each LED1402. A positive power source voltage VDD is input to the other terminalof each current limiting resistor 1406. The base of each transistor 1408is connected to the control circuit 150, and the transistor 1408 isswitched to be turned on and off by a switch signal input to the basefrom the control circuit 150.

The control circuit 150 has a central processing unit (CPU) 1502, a readonly memory (ROM) 1504, and a random access memory (RAM) 1506. Further,the control circuit 150 has a video controller 1508, an interface (I/F)1510, and a communication controller 1512. Furthermore, the controlcircuit 150 has a voltage regulator 1514. The CPU 1502, the ROM 1504,the RAM 1506, the video controller 1508, the I/F 1510, and thecommunication controller 1512 are connected to a common bus line 1516.

The CPU 1502 executes a program for controlling the operation of thefingerprint capture device 10 to control the operation of each unit ofthe fingerprint capture device 10. The ROM 1504 stores a programexecuted by the CPU 1502. Further, the RAM 1506 is a working area whenthe CPU 1502 executes a program.

The video controller 1508 is connected to the signal processing circuit1314 of the image sensor 130, and image data is input from the signalprocessing circuit 1314. The video controller 1508 transfers image datato the communication controller 1512 via the bus line 1516.

The timing generator 1304 of the image sensor 130 is connected to theI/F 1510. Thereby, the control signal by the CPU 1502 is input to thetiming generator 1304 via the I/F 1510. The timing generator 1304generates and outputs a timing signal based on a control signal inputvia the I/F 1510.

Further, the bases of the plurality of transistors 1408 in thenear-infrared light source 140 are connected to the I/F 1510. Thereby,the switch signal from the CPU 1502 is input to the base of thetransistors 1408 via the I/F 1510. The transistor 1408 is switched to beturned on and off based on a switch signal input via the I/F 1510. Inresponse to the transistor 1408 being switched to be turned on and off,the LED 1402 is switched to be turned on and off, and thereby thenear-infrared light source 140 is switched to be turned on and off.

Further, the capture switch 160 is connected to the I/F 1510. Inresponse to the capture switch 160 being pressed down, output of acontrol signal and a switch signal by the CPU 1502 is triggered.Further, in response to the capture switch 160 being pressed down, afingerprint image is recorded in the image processing apparatus 20 asdescribed later.

Specifically, in a non-operating state of the image sensor 130, thenear-infrared light source 140 is also in a turn-off state, and pressingdown of the capture switch 160 under this state causes the near-infraredlight source 140 to be turned off and start capturing a fingerprint bythe image sensor 130. The image sensor 130 that has started capturing afingerprint captures the fingerprint at a constant time interval andoutputs image data of the fingerprint image.

Further, once the capture switch 160 is pressed down during the imagesensor 130 being capturing a fingerprint at a constant time interval,the fingerprint image displayed on the display 214 in the imageprocessing apparatus 20 is recorded as described later. Then, when thefingerprint image has been recorded and the image sensor 130 enters anon-operating state, capturing of the fingerprint by the image sensor130 ends.

The communication controller 1512 functions as a transfer unitconfigured to transfer image data of the fingerprint image, whichtransfers image data transferred from the video controller 1508 to theimage processing apparatus 20 via the communication cable 30 connectedto the connector unit 170. The communication controller 1512 isconfigured to communicate with the image processing apparatus 20 via thecommunication cable 30 in accordance with a communication standard suchas Universal Serial Bus (USB) or the like, for example.

The communication cable 30 is configured to have two differential signallines for transmitting and receiving signals, a power source line forpower supply, and a ground line. The communication controller 1512transmits and receives signals through the two differential signal linesin the communication cable 30.

The power source line of the communication cable 30 is connected to thevoltage regulator 1514, and power is supplied via the power source linefrom a power source circuit 216 (see FIG. 5) in the image processingapparatus 20. The voltage regulator 1514 adjusts the voltage of thesupplied power and supplies it as a power source to each unit of thefingerprint capture device 10. The fingerprint capture device 10 is of abus-power system so as to operate by power supplied via thecommunication cable 30 from the image processing apparatus 20. Note thatthe fingerprint capture device 10 may be operated by power supplied froma built-in battery, for example, without limited to the bus-powersystem.

On the other hand, the image processing apparatus 20 functions as animage processing unit that performs processes such as display,recording, or the like on a fingerprint image transferred from thefingerprint capture device 10 that has captured a fingerprint. The imageprocessing apparatus 20 may be formed of a personal computer (PC) of alaptop type, a tablet type, or the like, for example. Further, imageprocessing apparatus 20 can control the operation of the fingerprintcapture device 10. Note that the image processing apparatus 20 is notnecessarily to be required to include the display 214 described later,and the image processing unit can be configured as including no displayunit.

The specific configuration of the image processing apparatus 20 will befurther described below by using FIG. 5 and FIG. 6. FIG. 5 is a blockdiagram illustrating the imaging processing apparatus 20. FIG. 6 is aschematic diagram illustrating a display window displayed on the imageprocessing apparatus 20.

As illustrated in FIG. 5, the image processing apparatus 20 has a CPU202, a ROM 204, a RAM 206, a hard disk drive (HDD) 208, and acommunication controller 210. Further, the image processing apparatus 20has a display controller 212 and the display 214. Further, the imageprocessing apparatus 20 has the power source circuit 216 and an inputdevice 218. The CPU 202, the ROM 204, the RAM 206, the HDD 208, thecommunication controller 210, display controller 212, the power sourcecircuit 216, and the input device 218 are connected to a common bus line220. Further, a connector unit 222 to which the communication cable 30is connected is provided to the image processing apparatus 20.

The CPU 202 controls the entire operation of the image processingapparatus 20. Further, the CPU 202 executes an image processing programused for display, recording, or the like of a fingerprint image acquiredby the fingerprint capture device 10. The image processing programperforms image processing on image data transferred from the fingerprintcapture device 10 and performs display, recording, or the like on afingerprint image thereof.

The ROM 204 stores therein a program such as a boot program. The RAM 206is used as a working area when the CPU 202 executes a program. Further,the RAM 206 functions as an image memory in which image data of afingerprint image transferred from the fingerprint capture device 10 istemporarily stored. The HDD 208 stores a program such as an imageprocessing program executed by the CPU 202.

Further, the HDD 208 functions as a recording unit that records afingerprint image captured by the fingerprint capture device 10. The CPU202 functions as a record control unit to record a fingerprint image inthe HDD 208. Note that the recording unit that records a fingerprintimage is not limited to the HDD 208 and, instead of the HDD 208, variousrecording devices may be used as the recording unit. The recording unitthat records a fingerprint image may be built in the image processingapparatus 20 similarly to the HDD 208 or may be an independent externalrecording device separate from the image processing apparatus 20.

The communication controller 210 functions as a receiving unit thatreceives image data of a fingerprint image to receive image datatransferred from the communication controller 1512 of the fingerprintcapture device 10 via the communication cable 30 connected to theconnector unit 222. The image data received by the communicationcontroller 210 is temporarily stored in the RAM 206 as an image memory.The communication controller 210 is configured to communicate with thefingerprint capture device 10 via the communication cable 30 inaccordance with a communication standard such as USB or the like, forexample, in association with the communication controller 1512. Thecommunication controller 210 is configured to transmit and receivesignals by two differential signal lines in the communication cable 30in association with the communication controller 1512.

Further, the display 214 that functions as a display unit that displaysa fingerprint image is connected to the display controller 212. Thedisplay controller 212 cooperates with the CPU 202 to function as adisplay control unit and renders and displays a display window of animage processing program executed by the CPU 202 on the display 214. Thedisplay window of the image processing program displayed on the display214 includes a preview window in which a captured fingerprint image isdisplayed. Note that, while not limited in particular, the display 214is a liquid crystal display, for example. Further, the display 214 maybe built in the image processing apparatus 20, which is a laptop PC, atablet PC, or the like, or may be an external display providedseparately from the image processing apparatus 20.

The power source circuit 216 supplies power of a built-in power sourceof the image processing apparatus 20 or power of an external powersource connected to the image processing apparatus 20 to the fingerprintcapture device 10. The power source circuit 216 is connected to thepower source line and the ground line of the communication cable 30 andsupplies power to the voltage regulator 1514 of the fingerprint capturedevice 10 via the power source line.

The input device 218 is a keyboard, a mouse, or the like, for example.Further, the input device 218 may be a touch panel embedded in thedisplay 214. An operator can input text information such as anidentification number (ID), a name, or the like of a subject or selectinformation regarding the type of a finger in the image processingprogram displayed on the display 214 via the input device 218. Further,setting of capturing conditions or the like may be performed.

FIG. 6 illustrates an example of a display window 300 of an imageprocessing program displayed on the display 214 of the image processingapparatus 20. As illustrated in FIG. 6, the display window 300 isprovided with a preview window 302, an identification number (ID) entryarea 304, a name entry area 306, a finger type selection area 308, arecording mode selection area 310, and an exposure level setting area312. Further, a latest-information display area 314 is provided in thedisplay window 300. Further, the display window 300 is provided with astart button 316, a preview button 318, a stop button 320, a folderselection button 322, and a next button 324.

The preview window 302 displays a preview of a fingerprint imagecaptured by the fingerprint capture device 10. In the preview window302, a fingerprint image can be displayed such that the light-dark ofridge line parts captured as bright parts and valley line parts capturedas dark parts is inverted in terms of visibility. Note that afingerprint image can be displayed without a change of the light-dark ofthe ridge line parts and the valley line parts captured by thefingerprint capture device 10.

The ID entry area 304 is an area to which an ID of a subject whosefingerprint is to be captured is input. The ID entry area 304 isprovided with an ID entry field 3042 to which an ID is input and tworadio buttons 3044 and 3046 used for selecting an entry scheme of theID. When the radio button 3044 labeled with “Auto ID” is selected, an IDcan be automatically input in the ID entry field 3042. Further, when theradio button 3046 labeled with “Manual ID” is selected, an ID can bemanually input in the ID entry field 3042 through the input device 218.For example, the input ID is utilized as a part of a file name of afingerprint image recorded in the HDD 208 or is recorded in a databasemanaged by the image processing program. Note that the database isrecorded in the HDD 208.

The name entry area 306 is an area to which the name of a subject whosefingerprint is to be captured is input. The name input area 306 isprovided with a family name input field 3062 to which a family name of asubject is input and a first name entry field 3064 to which a first nameof a subject is input. The input name is recorded in a database managedby an image processing program, for example.

The finger type selection area 308 is an area used for selecting thetype of a finger whose fingerprint is to be captured. The finger typeselection area 308 is provided with a finger type display field 3082 inwhich a finger type is displayed and switching buttons 3084 and 3086used for switching a finger type displayed in the finger type displayfield 3082. The finger type to be displayed in the finger type displayfield 3082 can be switched by pressing switching buttons 3084 and 3086.A finger type to be displayed can be switched and selected out of thethumbs, the index fingers, the middle fingers, the ring fingers, and thesmall fingers of the left hand and the right hand, respectively, and thefirst toes, the second toes, the third toes, the fourth toes, and thefifth toes of the left foot and the right foot, respectively, namely, 20fingers in total. The finger type displayed in the finger type displayfield 3082 and selected is utilized as a part of a file name of afingerprint image recorded in the HDD 208 or is recorded in a databasemanaged by the image processing program, for example.

The recording mode selection area 310 is an area used for selecting andsetting a mode by which a captured fingerprint image is recorded. Therecording mode selection area 310 is provided with two radio buttons3102 and 3104 used for selecting a recording mode. A recording modewhich records a fingerprint image in the HDD 208 can be set manually byselecting the radio button 3102 labeled with “Manual”, that is, inaccordance with a record instruction input by the capture switch 160 ofthe fingerprint capture device 10 as described later. Further, arecording mode which automatically records a fingerprint image in theHDD 208 can be set by selecting the radio button 3104 labeled with“Auto”. Note that, in the present example embodiment, a fingerprintimage is recorded manually as described later.

The exposure level setting area 312 is an area used for setting anexposure level when capturing a fingerprint by the fingerprint capturedevice 10. The exposure level setting area 312 is provided with, forexample, three radio buttons 3122, 3124, and 3126 used for setting anexposure level. For example, three radio buttons 3122, 3124, and 3126are labeled with “low”, “middle”, and “high”, respectively, and anexposure level can be set in three steps. Selection of the radio button3122 labeled with “low” allows the lowest exposure level to be set.Also, selection of the radio button 3126 labeled with “high” allows thehighest exposure level to be set. Also, selection of the radio button3124 labeled with “middle” allows the intermediate exposure level ofthree steps to be set. Note that an exposure level can be realized bychanging the capturing time period by the image sensor 130 or changingthe output of the near-infrared light source 140 in accordance with thesetting of the exposure level, for example.

In the latest-information display area 314, a file name of the latestfingerprint image recorded in the HDD 208 is displayed including a pathof a recording folder, for example. Further, in the latest-informationdisplay area 314, the latest fingerprint image recorded in the HDD 208is displayed, for example. Note that a folder of the HDD 208 in which afingerprint image is recorded can be selected from a folder selectionwindow displayed by pressing the folder selection button 322.Furthermore, the quality of a fingerprint image displayed in the previewwindow 302 or a recorded fingerprint image may be displayed in thelatest-information display area 314.

Further, in the display window 300, the state of the fingerprint capturedevice 10 can be checked by pressing the start button 316, and capturingby the fingerprint capture device 10 can be stopped by pressing the stopbutton 320. Furthermore, the fingerprint capture device 10 can bestarted up by pressing the preview button 318. Further, the ID in the IDentry field 3042 can be changed or cleared to move onto capturing afingerprint of the next subject by pressing the next button 324.

The fingerprint capture system 1 according to the present exampleembodiment is configured as above. In the fingerprint capture system 1according to the present example embodiment, when the capture switch 160provided in the fingerprint capture device 10 is pressed down, start ofcapturing, stop of capturing, or recording of a fingerprint image by thefingerprint capture device 10 is controlled.

Next, a fingerprint capture method using the fingerprint capture system1 according to the present example embodiment described above will befurther described by using FIG. 7 and FIG. 8. FIG. 7 is a flowchartillustrating a basic operation of the fingerprint capture system 1according to the present example embodiment. FIG. 8 is a timing chartillustrating the operation of the fingerprint capture device 10 and theimage processing apparatus 20 in the fingerprint capture system 1according to the present example embodiment.

First, prior to the description of the fingerprint capture methodaccording to the present example embodiment, the basic operation of thefingerprint capture system 1 will be described by using FIG. 7. Thebasic operation here corresponds to an operation until a fingerprintimage captured by the image capture device 10 is displayed on thedisplay 214 of the image processing apparatus 20. Further, in thefollowing description, a subject who performs capturing of his/herfingerprint by himself/herself and an assisting person who helpscapturing of the fingerprint of the subject are referred to as anoperator.

First, in a state where the fingerprint capture device 10 is stopped,the operator has the ball of his/her finger whose fingerprint is to becaptured come into contact with the sensor face 1202 of the fingerprintcapture device 10.

Next, in a state where the ball of the finger is in contact with thesensor face 1202 of the fingerprint capture device 10, the operatorpresses down the capture switch 160 provided to the fingerprint capturedevice 10 as illustrated in FIG. 7 (step S101). This first pressing downof the capture switch 160 causes a signal illustrating a captureinstruction that instructs capturing to be input to the fingerprintcapture device 10.

In response to the signal indicating the capture instruction input bythe first pressing down of the capture switch 160, the fingerprintcapture device 10 drives the image sensor 130 and turns on thenear-infrared light source 140. Thereby, the fingerprint capture device10 performs a capture operation of capturing a fingerprint image (stepS102). In the capture operation, the fingerprint capture device 10captures, repeatedly at a constant time interval, a fingerprint of thesame finger whose ball is in contact with the sensor face 1202. Whilevarying depending on the performance of the image sensor 130 used, thecapturing time period required for the fingerprint capture device 10 tocapture one fingerprint image is 0.6 to 1 second, for example.

Further, upon capturing a fingerprint image, the fingerprint capturedevice 10 performs a transfer operation of transferring image data ofthe captured fingerprint image to the image processing apparatus 20(step S103). In the transfer operation, the fingerprint capture device10 transfers image data of the captured fingerprint image to the imageprocessing apparatus 20 via the communication cable 30.

The image processing apparatus 20 to which image data of the fingerprintimage is transferred temporarily stores the image data in the RAM 206 asan image memory and then performs an image processing operation ofperforming predetermined image processing on the image data (step S104).

Next, the image processing apparatus 20 performs a display operation ofdisplaying a fingerprint image on the display 214 (step S105). In thedisplay operation, the image processing apparatus 20 displays afingerprint image for a predetermined display time on the display 214.In the display 214, a fingerprint image is displayed in the previewwindow 302 in the display window 300 of the image processing program.The display time in which a fingerprint image is displayed is the timeperiod enough for the operator to review the displayed fingerprint imageto determine whether or not the quality of the fingerprint image isgood.

The display time period in which one fingerprint image is displayed onthe display 214 is longer than or equal to the capturing time periodrequired for the fingerprint capture device 10 to capture onefingerprint image. For example, when the capturing time period perfingerprint image is 0.6 seconds, for example, the display time periodper fingerprint image on the display 214 can also be around 0.6 seconds,which is close the capturing time period. With such a length of displaytime period, the operator can review the quality of a fingerprint imagedisplayed on the display 214 to determine whether or not the qualitythereof is good.

Further, with a further longer display time period of a fingerprintimage than the capturing time period, the operator can thoroughlydetermine whether or not the quality of the fingerprint image is good.Thus, the display time period per fingerprint image can be set longerthan the capturing time period per fingerprint image. The time forhaving the display time period longer than the capturing time period maybe generated on the fingerprint capture device 10 side or may begenerated on the image processing apparatus 20 side. For example, adelay circuit that delays transfer of image data is provided in thefingerprint capture device 10 to delay the time required to transferimage data from the fingerprint capture device 10 to the imageprocessing apparatus 20, and thereby the display time can be increasedin accordance with the delay time. Further, also in the image processingapparatus 20, it is possible to generate the delay time in a hardwaremanner by using a delay circuit or the like or in a software manner byusing an image processing program or the like and increase the displaytime period in accordance with the delay time. However, since the longerthe display time period is, the lower the efficiency of acquiring afingerprint is, it is preferable to set the display time period taking aviewpoint of the efficiency of acquiring a fingerprint intoconsideration.

Once the capture switch 160 is pressed down, the fingerprint capturesystem 1 according to the present example embodiment repeats the basicoperation described above from capturing to display of a fingerprintimage for the same finger whose ball is in contact with the sensor face1202. Thereby, a plurality of fingerprint images of the same fingersequentially captured by the fingerprint capture device 10 aresequentially displayed for a predetermined display time period on thedisplay 214 of the image processing apparatus 20. In the display 214,after a fingerprint image is displayed for a predetermined display timeperiod, which is switched to the next display of another fingerprintimage. The fingerprint capture system 1 according the present exampleembodiment repeats the above-described basic operation until the captureswitch 160 is pressed down for the second time. When the capture switch160 is pressed down for the second time, the image processing apparatus20 performs a record operation of recording the fingerprint image.

A fingerprint capture method according to the present example embodimentincluding the record operation of the image processing apparatus 20 willbe described below by using FIG. 8. In the timing chart illustrated inFIG. 8, the horizontal axis represents time t. Further, in the timingchart illustrated in FIG. 8, among the first stage to the sixth stagearranged downward, solid-line frames in the first stage represent thecapture operation performed by the fingerprint capture device 10.Solid-line frames in the second stage represent the transfer operationperformed by the fingerprint capture device 10. Solid-line frames in thethird stage represent the image processing operation performed by theimage processing apparatus 20. Solid-line frames in the fourth stagerepresent the display operation performed by the image processingapparatus 20. Solid-line frames in the fifth stage represent the recordoperation performed by the image processing apparatus 20. Further, thenumbers N (where N is a natural integer) provided to the solid-lineframes on each stage of the first stage to the fifth stage indicate thatthe operation represented by the solid-line frame is an operation forthe N-th frame fingerprint image captured for the N-th time. Further, inthe sixth stage, it is indicated that the capture switch 160 of thefingerprint capture device 10 is pressed down at the time when a signaltransitions from a low level to a high level and thereby a pulse occurs.

As illustrated in FIG. 8, at the time t1, in response to the operatorpressing down the capture switch 160 for the first time, a signal S1indicating a startup instruction that instructs a startup is input tothe fingerprint capture device 10. Once the signal S1 indicating astartup instruction is input, the control circuit 150 supplies a powersource voltage to the image sensor 130 and starts up the image sensor130. The control circuit 150 turns on the transistor 1408 to turn on theLED 1402. Each pixel of the pixel array 1302 receives lights scatteredinside the finger and accumulates charges in accordance with the lightamount. The vertical scanning circuit 1306 scans the pixel array 1302 ona row basis, and the column amplifier circuit 1308 amplifies pixelsignals output from respective row. The A/D convertor circuit 1310converts pixel signals amplified by the column amplifier circuit 1308from an analog signal to a digital signal and outputs the pixel signalsto the signal processing circuit 314 sequentially in accordance with acontrol signal from the horizontal scanning circuit 1312. The signalprocessing circuit 1314 performs image processing such as correlateddouble sampling, shading correction, or the like on the pixel signal andaccumulates the pixel signals of the first frame as a fingerprint image.

At the time t2, upon the completion of capturing of the fingerprintimage of the first frame, the control circuit 150 starts transmittingthe fingerprint image of the first frame to the image processingapparatus 20 on a packet basis. That is, the video controller 1508sequentially reads out the fingerprint image accumulated in the signalprocessing circuit 1314 and sends it out to the communication controller1512. The communication controller 1512 divides the fingerprint imageinto packets and transmits the packets to the image processing apparatus20 via the communication cable 30. In the image processing apparatus 20,the communication controller 210 receives the fingerprint image on apacket basis, and the CPU 202 sequentially accumulates the receivedpackets in the RAM 206.

At the time t3, after the fingerprint capture device 10 has transmittedthe whole fingerprint image of the first frame to the image processingapparatus 20, the fingerprint capture device 10 starts capturing afingerprint image of the second frame. The image processing apparatus 20performs image processing on the fingerprint images accumulated in theRAM 206. The image processing may include, for example, a determinationprocess as to whether or not a fingerprint image is properly captured,in addition to noise removal, normalization of brightness values, andbinarization. Note that, while the image processing apparatus 20 isperforming image processing, the fingerprint capture device 10 capturesthe fingerprint image of the second frame.

At the time t4, upon the completion of image processing on thefingerprint image of the first frame, the image processing apparatus 20displays, on the display 214, the fingerprint image of the first frameresulted after the image processing. Meanwhile, the fingerprint capturedevice 10 transmits the fingerprint image of the second frame to theimage processing apparatus 20 on a packet basis, and the imageprocessing apparatus 20 performs image processing on the receivedfingerprint image.

At the time t5, upon the completion of image processing on thefingerprint image of the second frame, the image processing apparatus 20displays the fingerprint image of the second frame on the display 214.

The image processing apparatus 20 repeats the image processing operationand the display operation every time image data of the fingerprint imageis transferred from the fingerprint capture device 10 as describedabove. Meanwhile, the operator can review the fingerprint imagedisplayed on the display 214 of the image processing apparatus 20.Thereby, for the displayed fingerprint image, the operator can determinewhether or not the quality is good, respectively.

The operator reviews the quality of a plurality of fingerprint imagessequentially displayed on the display 214 and presses down the captureswitch 160 when a fingerprint image determined to be of high quality isdisplayed on the display 214. In FIG. 8, the fingerprint image of thefirst frame to the fingerprint image of the (N+5)-th frame aresequentially displayed on the display 214 with elapsing of time. Then,at the time t6 when the fingerprint image of the (N+5)-th frame isdisplayed, the operator determines that the fingerprint image of the(N+5)-th frame is of high quality and presses down the capture switch160 for the second time.

When the operator presses down the capture switch 160 for the secondtime, a signal S2 indicating a record instruction that instructsrecording of a fingerprint image is input to the image processingapparatus 20. When the signal S2 indicating a record instruction isinput, the image processing apparatus 20 records the fingerprint imagedisplayed on the display 214 in the HDD 208. Further, the imageprocessing apparatus 20 maintains a state where the fingerprint imagerecorded in the HDD 208 is displayed on the display 214. In FIG. 8, thefingerprint image of the (N+5)-th frame displayed on the display 214 atthe time t6 is recorded, and the state where the fingerprint image ofthe (N+5)-th frame is displayed on the display 214 is maintained.

When the operator presses down the capture switch 160 for the secondtime, the signal S2 indicating a record instruction is input, and asignal S3 indicating a stop instruction that instructs stop is input tothe fingerprint capture device 10. When the signal S3 indicating a stopinstruction is input, the fingerprint capture device 10 enters a stopstate to stop the capture operation or the transfer operation. In FIG.8, the transfer operation is stopped for the captured fingerprint imageof the (N+6)-th frame.

Accordingly, the fingerprint image displayed on the display 214 isrecorded in the HDD 208, and acquisition of a fingerprint image isstopped.

As discussed above, in the present example embodiment, the fingerprintimage displayed on the display 214 at the time when the capture switch160 is pressed down for the second time is recorded in the HDD 208. Atthe same time, the fingerprint capture device 10 stops power sourcesupply to the image sensor 130 to cause the image sensor 130 to enter astop state. The captured fingerprint image is kept on being displayed onthe display 214. According to the present example embodiment, since itis possible to review the quality of a fingerprint image on the display214 and then record the fingerprint image, a high quality fingerprintimage can be acquired.

In general, there is a predetermined delay time from the time when afingerprint is captured by the fingerprint capture device 10 to the timewhen image data of the captured fingerprint image is transferred to theimage processing apparatus 20 and the fingerprint image is displayed onthe display 214. This delay time is due to the time period required totransfer image data, the time period required for image processing, orthe like. In the present example embodiment, since it is necessary tocapture fingerprint images of various sizes from a newborn to an infantat a sufficient resolution, it is necessary to increase the number ofpixels of the image sensor 130. The image sensor 130 has a size of 2 cmin width and 3 cm in length and a pixel density of 1270 ppi, forexample. This causes a longer transfer time for image data of afingerprint image, and it may take 0.6 seconds per frame including thetransfer time and other processing time to transfer image data of afingerprint image with such a large number of pixels in the current USB2.0 standard, for example. Thus, if a fingerprint image currently beingcaptured or a fingerprint image subsequently captured by the fingerprintcapture device 10 were recorded in the HDD 208 in response to the secondpressing down of the capture switch 160, there would be an inconsistencybetween a fingerprint image to be recorded and a fingerprint image beingdisplayed on the display 214. Therefore, in such a case, the operator isunable to review the quality of a fingerprint image to be recorded inthe HDD 208 to determine whether or not the quality is good, and the lowquality fingerprint image may be recorded.

In contrast, in the present example embodiment, since a fingerprintimage displayed on the display 214 is recorded in the HDD 208 asdescribed above, the operator is able to review the quality of thefingerprint image on the display 214 to determine whether or not thequality is good.

In particular, when the subject is a child such as a newborn, an infant,or a young child, a sufficient contrast may not be obtained in thefingerprint image because the finger thereof is thin, small, soft, orthe like. Further, since children may move their finger during capturingdue to unstable behavior, brightness unevenness may occur or a part of afingerprint may be deleted in a fingerprint image. According to thepresent example embodiment, since it is possible to review the qualityof a fingerprint image to be recorded and then record the fingerprintimage, even when the subject is a child such as a newborn, an infant, ora young child, it is possible to review and determine the quality of aplurality of fingerprint images and record a high quality fingerprintimage among the plurality of fingerprint images.

Further, even with the shortened delay time described above allowed byan improved data transfer rate due to advancement of technologies, it isdesirable to ensure a sufficient display time period for the operator todetermine on the display 214 whether or not the quality of a fingerprintimage is good. In the present example embodiment, a fingerprint imagetransferred from the fingerprint capture device 10 to the imageprocessing apparatus 20 and displayed on the display 214 is recorded inthe HDD 208. Thus, according to the present example embodiment, asufficient display time period to determine whether or not the qualityis good can be ensured without restricted by the timing or the like ofcapturing by the fingerprint capture device 10.

Note that an image processing circuit may be provided to the fingerprintcapture device 10, and it is possible to perform image processing suchas binarization or the like on the fingerprint image by using the imageprocessing circuit and then transfer image data of the fingerprint imagefrom the fingerprint capture device 10 to the image processing apparatus20. This can improve the transfer speed of image data of fingerprintimages from the fingerprint capture device 10 to the image processingapparatus 20.

Further, when the subject is a child such as a newborn, an infant, or ayoung child, for example, repetition of capturing of fingerprint until ahigh quality fingerprint image is acquired may cause a large burden onthe subject. According to the present example embodiment, since thequality is reviewed on the display 214 and then the fingerprint image isrecorded in the HDD 208, retry of acquisition of fingerprint images canbe avoided. Therefore, according to the present example embodiment, ahigh quality fingerprint image can be acquired at a high efficiency.Thus, according to the present example embodiment, when the subject is achild such as a newborn, an infant, or a young child in particular, aburden on the subject can be reduced.

Second Example Embodiment

A fingerprint capture system and a fingerprint capture method accordingto a second example embodiment of the present invention will bedescribed by using FIG. 9. Note that similar elements to those in thefingerprint capture system and the fingerprint capture method accordingto the above-described first example embodiment are labeled with thesame reference numerals, and the description thereof will be omitted orsimplified.

The fingerprint capture system according to the present exampleembodiment is substantially similar to the fingerprint capture systemaccording to the first example embodiment. The fingerprint capturesystem according to the present example embodiment is different from thefingerprint capture system according to the first example embodiment inthat the image processing apparatus 20 reduces a plurality offingerprint images with a constant time interval and then displayed onthe display 214.

The fingerprint capture method using the fingerprint capture systemaccording to the present example embodiment will be described below byusing FIG. 9. FIG. 9 is a timing chart illustrating the operation of thefingerprint capture device 10 and the image processing apparatus 20 inthe fingerprint capture system according to the present exampleembodiment. Note that the detail of the horizontal axis and the detailof the first stage to the sixth stage arranged downward of the timingchart illustrated in FIG. 9 are the same as those of the timing chartillustrated in FIG. 8.

As illustrated in FIG. 9, at the time t1, in response to the operatorpressing down the capture switch 160 for the first time, in a similarmanner to the first example embodiment, pixel signals of the first frameare accumulated as a fingerprint image in the signal processing circuit1314.

At the time t2, upon the completion of capturing of the fingerprintimage of the first frame, in a similar manner to the first exampleembodiment, the control circuit 150 starts transmitting the fingerprintimage of the first frame to the image processing apparatus 20 on apacket basis. Further, in the image processing apparatus 20, thecommunication controller 210 receives the fingerprint image on a packetbasis, and the CPU 202 sequentially accumulates the received packets inthe RAM 206.

At the time t3, after the fingerprint capture device 10 has transmittedthe whole fingerprint image of the first frame to the image processingapparatus 20, in a similar manner to the first example embodiment, thefingerprint capture device 10 starts capturing a fingerprint image ofthe second frame. The image processing apparatus 20 performs imageprocessing on the fingerprint image accumulated in the RAM 206. Notethat, while the image processing apparatus 20 is performing imageprocessing, the fingerprint capture device 10 captures the fingerprintimage of the second frame.

At the time t4, upon the completion of image processing on thefingerprint image of the first frame, the image processing apparatus 20displays, on the display 214, the fingerprint image of the first frameresulted after the image processing. Meanwhile, the fingerprint capturedevice 10 transmits the fingerprint image of the second frame to theimage processing apparatus 20 on a packet basis, and the imageprocessing apparatus 20 performs image processing on the receivedfingerprint image.

Unlike the first example embodiment, however, at the time t5, even afterthe image processing apparatus 20 has completed the image processing onthe fingerprint image of the second frame, the image processingapparatus 20 continues to display the fingerprint image of the firstframe without displaying the fingerprint image of the second frame onthe display 214. Display of the fingerprint image of the first framecontinues until image processing of the third frame ends at the time t6.

At the time t6, upon the completion of image processing on thefingerprint image of the third frame, the image processing apparatus 20displays the fingerprint image of the image-processed third frame on thedisplay 214.

Accordingly, the image processing apparatus 20 repeats display of thesequentially captured multiple fingerprint images for every other frame.

As discussed above, in the present example embodiment, unlike the firstexample embodiment, the image processing apparatus 20 deletesimage-processed multiple fingerprint images at a constant time intervaland displays the reduced fingerprint images on the display 214. That is,the image processing apparatus 20 deletes the image-processed multiplefingerprint images every predetermined number of fingerprint images anddisplays the reduced fingerprint images on the display 214. In FIG. 9,the captured fingerprint images are reduced every other fingerprintimage and displayed. Since the fingerprint images are reduced everyother fingerprint image, the display time period per fingerprint imageis longer than in the case of the first example embodiment. Note thatthe number of fingerprint images to be deleted at a constant timeinterval may be one fingerprint image or may be a plurality offingerprint images captured continuously.

As discussed above, in the present example embodiment, not all of theplurality of fingerprint images sequentially captured by the fingerprintcapture device 10 are displayed on the display 214, and the plurality offingerprint images sequentially captured by the fingerprint capturedevice 10 are reduced at a constant time interval and displayed.Therefore, according to the present example embodiment, furthersufficient display time period is ensured for the operator to review thequality of the fingerprint image on the display 214 to determine whetheror not the quality is good. Therefore, according to the present exampleembodiment, acquisition of a high quality fingerprint image can befurther ensured.

In a similar manner to the first example embodiment, the operatorreviews the quality of a plurality of fingerprint images sequentiallydisplayed on the display 214 and presses down the capture switch 160when a fingerprint image determined to be of high quality is displayedon the display 214. In FIG. 9, the fingerprint image of the first frame,the fingerprint image of the third frame, . . . , a fingerprint image ofthe N-th frame, a fingerprint image of the (N+2)-th frame, and afingerprint image of the (N+4)-th frame are sequentially displayed onthe display 214 with elapsing of time. Then, at the time t7 when thefingerprint image of the (N+4)-th frame is displayed, the operatordetermines that the fingerprint image of the (N+4)-th frame is of highquality and presses down the capture switch 160 for the second time.

When the operator presses down the capture switch 160 for the secondtime, in a similar manner to the first example embodiment, a signal S2indicating a record instruction that instructs recording of afingerprint image is input to the image processing apparatus 20. Whenthe signal S2 indicating a record instruction is input, the imageprocessing apparatus 20 records the fingerprint image displayed on thedisplay 214 in the HDD 208 in a similar manner to the first exampleembodiment. Further, the image processing apparatus 20 maintains a statewhere the fingerprint image recorded in the HDD 208 is displayed on thedisplay 214. In FIG. 9, the fingerprint image of the (N+4)-th framedisplayed on the display 214 at the time t7 is recorded, and the statewhere the fingerprint image of the (N+4)-th frame is displayed on thedisplay 214 is maintained.

Further, when the operator presses down the capture switch 160 for thesecond time, the signal S2 indicating a record instruction is input, anda signal S3 indicating a stop instruction that instructs stop is inputto the fingerprint capture device 10 in a similar manner to the firstexample embodiment. When the signal S3 indicating a stop instruction isinput, the fingerprint capture device 10 enters a stop state to stop thecapture operation or the transfer operation in a similar manner to thefirst example embodiment. In FIG. 9, the transfer operation is stoppedfor the captured fingerprint image of the (N+6)-th frame.

Accordingly, the fingerprint image displayed on the display 214 isrecorded in the HDD 208, and acquisition of a fingerprint image isstopped.

Third Example Embodiment

A fingerprint capture system and a fingerprint capture method accordingto a third example embodiment of the present invention will be describedby using FIG. 10. Note that similar elements to those in the fingerprintcapture system and the fingerprint capture method according to theabove-described first example embodiment are labeled with the samereference numerals, and the description thereof will be omitted orsimplified.

The fingerprint capture system according to the present exampleembodiment is substantially similar to the fingerprint capture systemaccording to the first example embodiment. The fingerprint capturesystem according to the present example embodiment is different from thefingerprint capture system according to the first example embodiment inthat the image processing apparatus 20 determines whether or not thequality of fingerprint images is good and reduces the fingerprint imagesbased on the quality of the fingerprint images for display on thedisplay 214.

The fingerprint capture method using the fingerprint capture systemaccording to the present example embodiment will be described below byusing FIG. 10. FIG. 10 is a timing chart illustrating the operation ofthe fingerprint capture device 10 and the image processing apparatus 20in the fingerprint capture system according to the present exampleembodiment. Note that the detail of the horizontal axis and the detailof the first stage to the sixth stage arranged downward of the timingchart illustrated in FIG. 10 are the same as those of the timing chartillustrated in FIG. 8.

As illustrated in FIG. 10, at the time t1, in response to the operatorpressing down the capture switch 160 for the first time, in a similarmanner to the first example embodiment, pixel signals of the first frameare accumulated as a fingerprint image in the signal processing circuit1314.

At the time t2, upon the completion of capturing of the fingerprintimage of the first frame, in a similar manner to the first exampleembodiment, the control circuit 150 starts transmitting the fingerprintimage of the first frame to the image processing apparatus 20 on apacket basis. Further, in the image processing apparatus 20, thecommunication controller 210 receives the fingerprint image on a packetbasis, and the CPU 202 sequentially accumulates the received packets inthe RAM 206.

At the time t3, after the fingerprint capture device 10 has transmittedthe whole fingerprint image of the first frame to the image processingapparatus 20, in a similar manner to the first example embodiment, thefingerprint capture device 10 starts capturing a fingerprint image ofthe second frame. The image processing apparatus 20 performs imageprocessing on the fingerprint image accumulated in the RAM 206. Notethat, while the image processing apparatus 20 is performing imageprocessing, the fingerprint capture device 10 captures a fingerprintimage of the second frame.

At the time t4, upon the completion of image processing on thefingerprint image of the first frame, the image processing apparatus 20determines whether or not the quality of the fingerprint image of thefirst frame is good.

As discussed above, in the present example embodiment, unlike the firstexample embodiment, the image processing apparatus 20 performs an imageprocessing operation and functions as a quality determination unit thatdetermines whether or not the quality of a fingerprint image is good.The image processing apparatus 20 evaluates the contrast of afingerprint image, brightness unevenness, or the like by using an imageprocessing program and determines whether or not the quality of afingerprint image is good. As a result of the quality determination, theimage processing apparatus 20 determines that a fingerprint image havinga quality which does not satisfy a predetermined quality is a lowquality fingerprint image. Note that an image evaluation scheme used inthe quality determination of a fingerprint image in the image processingapparatus 20 is not limited in particular, and various image processingschemes may be used. For example, in a fingerprint image represented bybinary values, when the ratio of white regions and black regions is outof a predetermined range, it can be determined that no fingerprint iscaptured. Further, a typical fingerprint image may be pre-stored asmodel data, the similarity between the captured fingerprint image andthe model data may be calculated, and a frame whose similarity is out ofa standard may be removed.

As a result of the quality determination, for a plurality of fingerprintimages, the image processing apparatus 20 does not display fingerprintimages which is determined as a low quality fingerprint image andsequentially displays other fingerprint images having a quality above apredetermined quality on the display 214. In FIG. 10, the imageprocessing apparatus 20 determines a fingerprint image of the firstframe obtained after the quality determination as a fingerprint imagehaving a quality above the predetermined quality and displays thefingerprint image of the first frame on the display 214. Meanwhile, thefingerprint capture device 10 transmits a fingerprint image of thesecond frame to the image processing apparatus 20 on a packet basis, andthe image processing apparatus 20 performs image processing and qualitydetermination on the received fingerprint image.

At the time t5, the image processing apparatus 20 completes the imageprocessing and quality determination on the fingerprint image of thesecond frame. As a result, when determining the fingerprint image of thesecond frame as a low quality fingerprint image, the image processingapparatus 20 does not display the fingerprint image of the second frameon the display 214. In this case, the image processing apparatus 20continues to display the fingerprint image of the first frame.

Furthermore, at the time t6, the image processing apparatus 20 completesprocessing and quality determination on a fingerprint image capturedafter the fingerprint image of the second frame. As a result, whendetermining the fingerprint image of a third frame as a low qualityfingerprint image, the image processing apparatus 20 does not displaythe fingerprint image of the third frame on the display 214. In thiscase, the image processing apparatus 20 continues to display thefingerprint image of the first frame.

The display of the fingerprint image of the first frame is continueduntil a fingerprint image of a new frame is determined as a fingerprintimage having a quality above a predetermined quality.

At the time t6, upon the completion of image processing on thefingerprint image of the third frame, the image processing apparatus 20displays the image-processed fingerprint image of the third frame on thedisplay 214.

As a result of the quality determination, out of a plurality offingerprint images, the image processing apparatus 20 does not displayfingerprint images determined to be low quality fingerprint images andsequentially displays the remaining fingerprint images above apredetermined quality on the display 214, as described above. In FIG.10, out of the captured fingerprint images, the fingerprint image of thesecond frame, the fingerprint image of the third frame, the fingerprintimage of a (N+2)-th frame, and the fingerprint image of a (N+3)-th frameare determined as low quality fingerprint images, respectively, and noneof which is displayed.

As discussed above, according to the present example embodiment, sincefingerprint images having a quality above a predetermined quality out ofa plurality of fingerprint images are displayed on the display 214, theoperator can select a higher quality fingerprint image from thedisplayed fingerprint images in a more reliable manner. Therefore,according to the present example embodiment, acquisition of a highquality fingerprint image can be further ensured.

In a similar manner to the first example embodiment, the operatorreviews the quality of a plurality of fingerprint images sequentiallydisplayed on the display 214 and presses down the capture switch 160when a fingerprint image determined to be of high quality is displayedon the display 214. In FIG. 10, the fingerprint image of the firstframe, . . . , the fingerprint image of the N-th frame, the fingerprintimage of the (N+1)-th frame, a fingerprint image of the (N+4)-th frame,and a fingerprint image of the (N+5)-th frame are sequentially displayedon the display 214 with elapsing of time. Then, at the time t7 when thefingerprint image of the (N+5)-th frame is displayed, the operatordetermines that the fingerprint image of the (N+5)-th frame is of highquality and presses down the capture switch 160 for the second time.

When the operator presses down the capture switch 160 for the secondtime, in a similar manner to the first example embodiment, a signal S2indicating a record instruction that instructs recording of fingerprintimages is input to the image processing apparatus 20. When the signal S2indicating a record instruction is input, the image processing apparatus20 records the fingerprint image displayed on the display 214 in the HDD208 in a similar manner to the first example embodiment. Further, theimage processing apparatus 20 maintains a state where the fingerprintimage recorded in the HDD 208 is displayed on the display 214. In FIG.10, the fingerprint image of the (N+5)-th frame displayed on the display214 at the time t7 is recorded, and the state where the fingerprintimage of the (N+5)-th frame is displayed on the display 214 ismaintained.

Further, when the operator presses down the capture switch 160 for thesecond time, and a signal S3 indicating a stop instruction thatinstructs stop is input to the fingerprint capture device 10 in asimilar manner to the first example embodiment. When the signal S3indicating a stop instruction is input, the fingerprint capture device10 enters a stop state to stop the capture operation or the transferoperation in a similar manner to the first example embodiment. In FIG.10, the transfer operation is stopped for the captured fingerprint imageof the (N+6)-th frame.

Accordingly, the fingerprint image displayed on the display 214 isrecorded in the HDD 208, and acquisition of a fingerprint image isstopped.

Note that, while the case where the image processing apparatus 20performs quality determination on a fingerprint image before it isdisplayed on the display 214 has been described above, the timing of thequality determination by the image processing apparatus 20 is notlimited thereto.

For example, the first or second example embodiment described above maybe configured such that the image processing apparatus 20 determineswhether or not the quality of a fingerprint image that the operator hasinstructed to record in the HDD 208. In this case, when the quality ofthe fingerprint image that the operator has instructed to record in theHDD 208 is less than a predetermined quality, the image processingapparatus 20 displays, on the display 214, an alert display notifyingthat the fingerprint image quality is low. Further, instead of or inaddition to display of an alert indication on the display 214, the imageprocessing apparatus 20 may sound an alert sound notifying that thefingerprint image quality is low. Such an alert indication or an alertsound can urge the operator to again acquire a fingerprint image.

Fourth Example Embodiment

A fingerprint capture system and a fingerprint capture method accordingto a fourth example embodiment of the present invention will bedescribed by using FIG. 11. Note that similar elements to those in thefingerprint capture system and the fingerprint capture method accordingto the above-described first example embodiment are labeled with thesame reference numerals, and the description thereof will be omitted orsimplified.

The fingerprint capture system according to the present exampleembodiment is substantially similar to the fingerprint capture systemaccording to the first example embodiment. The fingerprint capturesystem according to the present example embodiment displays, on thedisplay 214, a fingerprint image captured at a time of pressing down thecapture switch 160 and fingerprint images captured before and/or afterthe time, out of a plurality of fingerprint images repeatedly capturedby the fingerprint capture device 10. The fingerprint capture systemaccording to the present example embodiment is different in this featurefrom the fingerprint capture system according to the first exampleembodiment.

The fingerprint capture method using the fingerprint capture systemaccording to the present example embodiment will be described below byusing FIG. 11. FIG. 11 is a timing chart illustrating the operation ofthe fingerprint capture device and the image processing apparatus in thefingerprint capture system according to the present example embodiment.In the timing chart illustrated in FIG. 11, the horizontal axisrepresents time t. Further, in the timing chart illustrated in FIG. 11,among the first stage to the fifth stage arranged downward, solid-lineframes in the first stage collectively represent the capture operationand transfer operation performed by the fingerprint capture device 10.Solid-line frames in the second stage represent the temporary storageoperation described later of a plurality of fingerprint images performedby the image processing apparatus 20. Solid-line frames in the thirdstage represent the display operation performed by the image processingapparatus 20. Solid-line frames in the fourth stage represent the recordoperation performed by the image processing apparatus 20. Further, thenumbers N provided to the solid-line frames on each stage of the firststage to the fourth stage are the same as the first example embodimentdescribed above. Further, in the fifth stage, it is indicated that thecapture switch 160 of the fingerprint capture device 10 is pressed downat the time when a signal transitions from a low level to a high leveland thereby a pulse occurs.

As illustrated in FIG. 11, at the time t1, in response to the operatorpressing down the capture switch 160 for the first time, the fingerprintcapture device 10 repeats the capture operation and the transferoperation, which is the same as the first example embodiment. Note that,in the first stage of the timing chart illustrated in FIG. 11, a captureoperation and a transfer operation are collectively represented as asingle solid frame.

Subsequently, at the time t2, in response to the operator pressing downthe capture switch 160 for the second time, a signal S4 indicating atemporary storage instruction that instructs temporary storage of afingerprint image is input to the image processing apparatus 20. Inresponse to the input of the signal S4 indicating a temporary storageinstruction, the image processing apparatus 20 performs the temporarystorage operation for the sequentially captured multiple fingerprintimages. The operator is able to press down the capture switch 160 in thesecond time at a timing when determining it as suitable to capture afingerprint image. For example, when an assisting person assistscapturing of a fingerprint of a subject, the assisting person is able topress down the capture switch for the second time at a timing whendetermining that the finger of the subject is fixed at a positionsuitable for capturing the fingerprint.

In the temporary storage operation, the image processing apparatus 20temporarily stores, in the RAM 206 functioning as an image memory, thesequentially captured multiple fingerprint images as fingerprint imagesto be displayed on the display 214. Specifically, the image processingapparatus 20 temporarily stores, in the RAM 206, a fingerprint imagecaptured by the fingerprint capture device 10 at a time when the captureswitch 160 is pressed down in the second time and fingerprint imagescaptured before and/or after the time. In FIG. 11, a fingerprint imageof the N-th frame captured at the time when the capture switch 160 ispressed down for the second time is temporarily stored. Further, twofingerprint images of the (N−2)-th frame and the (N−1)-th frame capturedbefore the fingerprint image of the N-th frame are temporarily stored.Further, two fingerprint images of the (N+1)-th frame and the (N+2)-thframe captured after the fingerprint image of the N-th frame aretemporarily stored.

Note that the fingerprint capture device 10 enters a stop state afterthe capture switch 160 is pressed down for the second time and thepreset number of fingerprint images are captured. In FIG. 11, thefingerprint capture device 10 enters a stop state to stop the captureoperation and the transfer operation after the fingerprint image of theN-th frame is captured and the two fingerprint images of the (N+1)-thframe and the (N+2)-th frame are then captured.

Subsequently, the image processing apparatus 20 performs an imageprocessing operation and then a display operation on a plurality offingerprint images stored in the temporary storage operation andsequentially displays these plurality of fingerprint images on thedisplay 214. Note that the image processing operation is omitted in FIG.11. The display time period in which the one fingerprint image isdisplayed on the display 214 is a time period that is longer than orequal to a capturing time period required for the fingerprint capturedevice 10 to capture one fingerprint image and may be a longer timeperiod than the capturing time period, in the similar manner to thefirst example embodiment. Note that, instead of sequentially displayinga plurality of fingerprint images, a plurality of fingerprint images maybe collectively listed as thumbnails.

The operator reviews the quality of a plurality of fingerprint imagessequentially displayed on the display 214 in a similar manner to thefirst example embodiment and presses down the capture switch 160 whenthe fingerprint image displayed on the display 214 is determined to beof high quality. In FIG. 11, the fingerprint image of the (N−2)-thframe, the fingerprint image of the (N−1)-th frame, the fingerprintimage of the N-th frame, the fingerprint image of the (N+1)-th frame,and the fingerprint image of the (N+2)-th frame are sequentiallydisplayed on the display 214 with elapsing of time. At the time t3 whenthe fingerprint image of the (N+1)-th frame is displayed, the operatordetermines that the quality of the fingerprint image of the (N+1)-thframe is high and presses down the capture switch 160 for the thirdtime.

When the operator presses down the capture switch 160 for the thirdtime, in a similar manner to the first example embodiment, a signal S2indicating a record instruction that instructs recording of afingerprint image is input to the image processing apparatus 20. Whenthe signal S2 indicating a record instruction is input, the imageprocessing apparatus 20 records the fingerprint image displayed on thedisplay 214 in the HDD 208 in a similar manner to the first exampleembodiment. In FIG. 11, the fingerprint image of the (N+1)-th framedisplayed on the display 214 at the time t3 is recorded.

Note that, after the third pressing down of the capture switch 160, theimage processing apparatus 20 may continue the display operation for afingerprint image which has not yet been displayed out of the pluralityof fingerprint images and subsequently give the operator opportunitiesof determining whether or not the fingerprint image quality is good. Inthis case, by the capture switch 160 being pressed down for the fourthtime, the fingerprint image displayed on the display 214 is now recordedin the HDD 208. Further, instead of such a display operation, the imageprocessing apparatus 20 may maintain a state where the fingerprint imagerecorded in the HDD 208 by the third pressing down of the capture switch160 is displayed on the display 214.

Accordingly, the fingerprint image displayed on the display 214 isrecorded in the HDD 208, and acquisition of a fingerprint image isstopped.

In the present example embodiment, not only a fingerprint image capturedat a time when the capture switch 160 is pressed down for the secondtime but also fingerprint images captured before and/or after the timeare displayed on the display 214. The second pressing down of thecapture switch 160 can be made at a timing when the operator determinesit as suitable for capturing a fingerprint image. Then, operator canreview the quality of a plurality of fingerprint images displayed insuch a way to determine whether or not the quality thereof is good.

Even when a fingerprint image is captured at a timing that the operatordetermines as suitable for capturing a fingerprint image, the quality ofthe fingerprint image actually captured is likely to be low. In thisregard, in the present example embodiment, a fingerprint image to berecorded in the HDD 208 can be selected from a plurality of fingerprintimages including not only a fingerprint image captured at a timing thatthe operator determines as appropriate but also fingerprint imagescaptured before and/or after the time. Therefore, according to thepresent example embodiment, a higher quality fingerprint image can beacquired.

Other Example Embodiments

The image processing apparatus 20 according to the example embodimentsdescribed above can be implemented based on a computer program executedby a CPU of a computer. Such a program can be created as a program thatcauses a computer to execute steps for implementing respectiveoperations and respective processes described in the example embodimentsdescribed above. A part of or a whole of the program can be provided asa computer readable storage medium recording it, such as a DigitalVersatile Disc-Read Only Memory (DVD-ROM), a Compact Disc-Read OnlyMemory (CD-ROM), a flash memory such as a USB memory, or the like.

Further, the fingerprint capture system described in each of the aboveexample embodiments can also be configured as illustrated in FIG. 12according to another example embodiment. FIG. 12 is a block diagramillustrating a functional configuration of a fingerprint capture systemaccording to another example embodiment.

As illustrated in FIG. 12, a fingerprint capture system 4000 accordingto another example embodiment has a capture unit 4002 that captures afingerprint and an image processing unit 4004 to which a fingerprintimage of the fingerprint captured by the capture unit 4002 istransferred and that processes the fingerprint image. Further, thefingerprint capture system 4000 has a display unit 4006 on which thefingerprint image transferred to the image processing unit 4004 isdisplayed and a recording unit 4008 in which the fingerprint imagetransferred to the image processing unit 4004 is recorded by the imageprocessing unit 4004. Furthermore, the fingerprint capture system 4000has an instruction unit 4010 that inputs, in the image processing unit4004, a record instruction that instructs the image processing unit 4004to record the fingerprint image in the recording unit 4008. The imageprocessing unit 4004 records, in the recording unit 4008, thefingerprint image displayed on the display unit 4006 at the time whenthe record instruction is input by the instruction unit 4010.

According to the fingerprint capture system 4000 of another exampleembodiment, a high quality fingerprint image can be acquired.

Further, the fingerprint capture device described in each of the aboveexample embodiments can also be configured as illustrated in FIG. 13according to another example embodiment. FIG. 13 a block diagramillustrating a functional configuration of a fingerprint capture deviceaccording to another example embodiment.

As illustrated in FIG. 13, a fingerprint capture device 5000 accordingto another example embodiment has a sensor unit 5002 that captures afingerprint and a transfer unit 5004 that transfers a fingerprint imageto an image processing unit in order to display a fingerprint image of afingerprint captured by the sensor unit 5002 on a display unit. Further,the fingerprint capture device 5000 has an instruction unit 5006 thatinputs, to the image processing unit, a record instruction thatinstructs recording of a fingerprint image transferred to the imageprocessing unit and displayed on the display unit into a recording unit.

According to the fingerprint capture device 5000 of another exampleembodiment, a high quality fingerprint image can be acquired.

Further, the image processing apparatus described in each of the aboveexample embodiments can also be configured as illustrated in FIG. 14according to another example embodiment. FIG. 14 a block diagramillustrating a functional configuration of an image processing apparatusaccording to another example embodiment.

As illustrated in FIG. 14, an image processing apparatus 6000 accordingto another example embodiment has a receiving unit 6002 that receives afingerprint image of a fingerprint captured by a capture unit thatcaptures a fingerprint and a display control unit 6004 that displays thefingerprint image received by the receiving unit 6002 on a display unit.Furthermore, the image processing apparatus 600 has a record controlunit 6006 that records the fingerprint image in a recording unit basedon a record instruction that instructs recording of the fingerprintimage displayed on the display unit in the recording unit.

According to the image processing apparatus 6000 of another exampleembodiment, a high quality fingerprint image can be acquired.

Modified Example Embodiments

Further, the present invention is not limited to the example embodimentsdescribed above, and various modifications are possible.

For example, while the case where the fingerprint capture device 10captures a fingerprint by utilizing a near-infrared light has beendescribed as an example in the above example embodiments, thefingerprint capture device 10 is not necessarily limited to thoseutilize a near-infrared light as long as the fingerprint capture devicecaptures a fingerprint.

Further, while the case where the fingerprint capture device 10 acquiresa fingerprint of a single finger has been described as an example in theabove example embodiments, it is possible to capture fingerprint imagesof a plurality of fingers at the same time.

Further, while the case where the capture switch 160 is provided on thebottom face of the holding portion 1102 of the casing 110 has beendescribed as an example in the above example embodiments, the positionwhere the capture switch 160 is provided is not limited thereto. Forexample, the capture switch 160 may be provided on the side face of theholding unit 1102.

The part or whole of the example embodiments disclosed above can bedescribed as, but not limited to, the following supplementary notes.

(Supplementary Note 1)

A fingerprint capture system comprising:

a capture unit that captures a fingerprint;

an image processing unit to which a fingerprint image of the fingerprintcaptured by the capture unit is transferred and that processes thefingerprint image;

a display unit on which the fingerprint image transferred to the imageprocessing unit is displayed;

a recording unit in which the fingerprint image transferred to the imageprocessing unit is recorded by the image processing unit; and

an instruction unit that inputs, in the image processing unit, a recordinstruction that instructs the image processing unit to record thefingerprint image in the recording unit,

wherein the image processing unit records, in the recording unit, thefingerprint image displayed on the display unit at a time when therecord instruction is input by the instruction unit.

(Supplementary Note 2)

The fingerprint capture system according to supplementary note 1,

wherein the capture unit sequentially captures a plurality offingerprint images for a same finger, and

wherein the plurality of fingerprint images are sequentially displayedon the display unit each for a display time period that is longer thanor equal to a capturing time period required for the capture unit tocapture each one of the fingerprint images.

(Supplementary Note 3)

The fingerprint capture system according to supplementary note 2,wherein the plurality of fingerprint images are reduced at a constanttime interval and sequentially displayed on the display unit.

(Supplementary Note 4)

The fingerprint capture system according to any one of supplementarynotes 1 to 3, wherein the image processing unit determines whether ornot a quality of the fingerprint image that the instruction unit hasinstructed to record in the recording unit is good.

(Supplementary Note 5)

The fingerprint capture system according to supplementary note 1,

wherein the capture unit sequentially captures a plurality offingerprint images for a same finger,

wherein the image processing unit determines whether or not each qualityof the plurality of fingerprint images is good, and

wherein, out of the plurality of fingerprint images on which whether ornot a quality is good has been determined by the image processing unit,the fingerprint images above a predetermined quality are sequentiallydisplayed on the display unit.

(Supplementary Note 6)

The fingerprint capture system according to supplementary note 1,

wherein the capture unit sequentially captures a plurality offingerprint images for a same finger,

wherein, before the record instruction, the instruction unit inputs, tothe image processing unit, a temporary storage instruction thatinstructs the image processing unit to temporarily store the fingerprintimage,

wherein the image processing unit temporarily stores the fingerprintimage captured by the capture unit at a time when the temporary storageinstruction is input and the fingerprint images captured before and/orafter the time, and

wherein the plurality of fingerprint images temporarily stored by theimage processing unit are displayed on the display unit.

(Supplementary Note 7)

The fingerprint capture system according to any one of supplementarynotes 1 to 5, wherein the instruction unit inputs the record instructionand inputs, to the capture unit, a stop instruction that instructs thecapture unit to stop.

(Supplementary Note 8)

The fingerprint capture system according to any one of supplementarynotes 1 to 7, wherein the instruction unit is provided in the captureunit.

(Supplementary Note 9)

A fingerprint capture device comprising:

a sensor unit that captures a fingerprint;

a transfer unit that, in order to display a fingerprint image of thefingerprint captured by the sensor unit on a display unit, transfers thefingerprint image to an image processing unit; and

an instruction unit that inputs, into the image processing unit, arecord instruction that instructs recording of the fingerprint imagetransferred to the image processing unit and displayed on the displayunit into a recording unit.

(Supplementary Note 10)

An image processing apparatus comprising:

a receiving unit that receives a fingerprint image of a fingerprintcaptured by a capture unit that captures the fingerprint;

a display control unit that displays the fingerprint image received bythe receiving unit on a display unit; and

a recording control unit that, based on a record instruction thatinstructs recording of the fingerprint image displayed on the displayunit in a recording unit, records the fingerprint image in the recordingunit.

(Supplementary Note 11)

A fingerprint capture method comprising:

capturing a fingerprint;

transferring a fingerprint image of the captured fingerprint;

displaying the transferred fingerprint image;

recording the transferred fingerprint image; and

inputting a record instruction that instructs recording of thefingerprint image,

wherein the recording of the fingerprint image records the fingerprintimage displayed at a time when the record instruction is input.

(Supplementary Note 12)

A storage medium in which a program is stored, the program causing acomputer that processes a fingerprint image transferred from afingerprint capture device that captures a fingerprint to execute:

displaying a fingerprint image transferred from the fingerprint capturedevice; and

recording the fingerprint image transferred from the fingerprint capturedevice, wherein the recording records the fingerprint image displayed ata time when a record instruction that instructs recording of thefingerprint image is input.

While the present invention has been described above with reference tothe example embodiments, the present invention is not limited to theexample embodiments described above. Various changes that can beappreciated by those skilled in the art within the scope of the presentinvention may be applied to the configuration or the detail of thepresent invention.

REFERENCE SIGNS LIST

-   1 fingerprint capture system-   10 fingerprint capture device-   130 two-dimensional image sensor-   160 capture switch-   20 image processing apparatus-   214 display

The invention claimed is:
 1. A fingerprint image processing devicecomprising: a memory; and a processor coupled to the memory andconfigured to: receive a plurality of fingerprint images of a samefingerprint which are sequentially captured and sequentially transmittedby an imaging sensor; store the received plurality of fingerprint imagesinto a temporary storage; display at least one of the plurality offingerprint images sequentially one by one on a fingerprint displayregion in a screen of a display unit; receive an input of a recordinstruction which instructs to record a fingerprint image in anon-transitory storage; and when the input of the record instruction isreceived, execute: specifying, as a designated fingerprint image, afingerprint image that is displayed on the fingerprint display region ata timing when the input of the record instruction is received;determining whether or not quality of the designated fingerprint imageis better than a predetermined criterion of quality; and displaying,when the quality of the designated fingerprint image is not better thanthe predetermined criterion, information indicating that the quality ofthe designated fingerprint image is not better than the predeterminedcriterion to urge an operator who input the record instruction to thefingerprint image processing device to input the record instructionagain.
 2. The fingerprint image processing device according to claim 1,wherein the processor is configured to display each fingerprint image ofthe at least one of the plurality of fingerprint images on thefingerprint display region for time period enough for the operator toreview the displayed fingerprint image to determine whether or notquality of the displayed fingerprint image is acceptable.
 3. Thefingerprint image processing device according to claim 1, wherein theprocessor is configured to display each fingerprint image of the atleast one of the plurality of fingerprint images on the fingerprintdisplay region for at least 0.6 seconds.
 4. A fingerprint imageprocessing device comprising: receiving a plurality of fingerprintimages of a same fingerprint which are sequentially captured andsequentially transmitted by an imaging sensor; storing the receivedplurality of fingerprint images into a temporary storage; displaying atleast one of the plurality of fingerprint images sequentially one by oneon a fingerprint display region in a screen of a display unit; receivingan input of a record instruction which instructs to record a fingerprintimage in a non-transitory storage; and when the input of the recordinstruction is received, executing: specifying, as a designatedfingerprint image, a fingerprint image that is displayed on thefingerprint display region at a timing when the input of the recordinstruction is received; determining whether or not quality of thedesignated fingerprint image is better than a predetermined criterion ofquality; and displaying, when the quality of the designated fingerprintimage is not better than the predetermined criterion, informationindicating that the quality of the designated fingerprint image is notbetter than the predetermined criterion to urge an operator who inputthe record instruction to the fingerprint image processing device toinput the record instruction again.
 5. The fingerprint image processingdevice according to claim 4, comprising displaying each fingerprintimage of the at least one of the plurality of fingerprint images on thefingerprint display region for time period enough for the operator toreview the displayed fingerprint image to determine whether or notquality of the displayed fingerprint image is acceptable.
 6. Thefingerprint image processing device according to claim 4, comprisingdisplaying each fingerprint image of the at least one of the pluralityof fingerprint images on the fingerprint display region for at least 0.6seconds.
 7. A non-transitory computer-readable storage medium storing aprogram that causes a computer to perform: receiving a plurality offingerprint images of a same fingerprint which are sequentially capturedand sequentially transmitted by an imaging sensor; storing the receivedplurality of fingerprint images into a temporary storage; displaying atleast one of the plurality of fingerprint images sequentially one by oneon a fingerprint display region in a screen of a display unit; receivingan input of a record instruction which instructs to record a fingerprintimage in a non-transitory storage; and when the input of the recordinstruction is received, executing: specifying, as a designatedfingerprint image, a fingerprint image that is displayed on thefingerprint display region at a timing when the input of the recordinstruction is received; determining whether or not quality of thedesignated fingerprint image is better than a predetermined criterion ofquality; and displaying, when the quality of the designated fingerprintimage is not better than the predetermined criterion, informationindicating that the quality of the designated fingerprint image is notbetter than the predetermined criterion to urge an operator who inputthe record instruction to the fingerprint image processing device toinput the record instruction again.
 8. The storage medium according toclaim 7, wherein the program causes the computer to perform displayingeach fingerprint image of the at least one of the plurality offingerprint images on the fingerprint display region for time periodenough for the operator to review the displayed fingerprint image todetermine whether or not quality of the displayed fingerprint image isacceptable.
 9. The storage medium according to claim 7, wherein theprogram causes the computer to perform displaying each fingerprint imageof the at least one of the plurality of fingerprint images on thefingerprint display region for at least 0.6 seconds.